Haemophilia A and haemophilia B are both X linked recessive disorders of coagulation. 1/3 of cases have no family history.
Haemophilia A
- Incidence 1 in 10 000
- Lack of factor VIII
Haemophilia B = Christmas disease
- Incidence 1 in 50 000
- Lack of factor IX
Severity of the disease is classified according to the baseline level of clotting factor:
- Severe <1% normal
- Moderate 1-4% normal
- Mild 5 -50% normal
Complications include:
- Haemarthrosis (70-80%) – commonest joint affected is the knee followed by elbow
- Bleeds into muscle/soft tissue
- Haemophiliac arthropathy
- Intracranial haemorrhage
- Pseudotumours of bone
Management:
- Avoid use of NSAIDs/ASA
- Avoid IM injections
- Avoid contact sports
- Desmopressin
- Tranexamic acid
- Recombinant factor VIII or IX
- Vaccination against hepatitis A and B
Small print gem: female carriers may have menorrhagia
References: